|
Calculating Speed and Velocity
The
trouble with facts is that there are so many of them.
|
|
Whenever
we work on solving any motion problems we will be working with an equation
that requires a step-by-step method.
|
|
Careful
attention needs to be paid to writing out the known and unknown
measurements, the SI units involved, and the entering of numbers into your
calculator. Double check all work!
|
No
need to ask the question "Do we have to show all of our work?"
The
unqualified answer to that question is YES !
Numbers
mean nothing in measurements and science calculations if they are not
labeled with some type of unit.
Physics problems mean nothing without proof of your answer and that comes
with writing out the equation.
So let's get to it!
|
SPEED
and VELOCITY EQUATION:
speed = distance
OR
v = d
time
t
|
Remember
that the SI unit for speed and velocity is meters per second (m/s).
Velocity answers also require a direction.
The best way to learn the steps is to work through a problem.
If you need to review solving one step equations, click on the link
below.
|
Problem :
What is the speed of a sailboat that is traveling 100 meters in
120 seconds?
|
|
Step 1 : Write down the equation
you need to solve the problem.
|
v
= d
t
|
Step 2 : Place the known
information into the equation.
|
Known : The sailboat traveled a
distance of 100 meters and the time it took to travel that distance was 120
seconds. Since meters per second is the SI unit for speed, there is
no need for conversions in this problem.
v
= 100m =
120
s
|
Step 3 : Solve. Carefully enter
the numbers into your calculator. Remember that this is a division problem.
Check to make sure that your solution contains the correct SI unit.
|
SOLUTION : The sailboat
has a speed of .83m/s.
|
One
more example problem and then you will practice on your own.
|
Problem :
If a cyclist in the Tour de France traveled southwest a distance
of 12,250 meters in one hour, what would the velocity of the cyclist be?
|
|
Remember that the SI unit for velocity is meters per
second, but this problem has the distance measure in meters and the time
measured in hours. The 1 hour has to be converted to seconds.
If you need to review conversions, click here. Also, this is a
velocity problem and your solution requires a direction.
|
Step 1 : Write down the equation
needed for the problem.
|
v=
d
t
|
Step 2 : Enter all the known
values into the equation, taking care to make all necessary conversions.
|
v
= 12,250 m =
3,200s
|
Step 3 : Use your calculator to solve
the problem. Check to make sure that you included the correct SI unit and
direction.
|
SOLUTION :
3.83
m/s southwest
|
|
Ok guys that is
calculating of velocity,, and many in
our dialy life, right?
oke okta,,
BalasHapusi want to ask you,,
if the mass of the object increases does affect the speed? what happened to the speed?
oke okta, can you give us the explanation meaning of velocity before you give us the equation?
BalasHapus